We have four entry points that deal with the parents of display:none/ display:contents content. These are the functions for setting, changing, getting and removing a style context. Or more specifically:
GetStyleContextInMap called by GetDisplay[None|Contents]StyleFor
SetStyleContextInMap called by RegisterDisplay[None|Contents]StyleFor
ChangeStyleContextInMap called by ChangeRegisteredDisplay[None|Contents]StyleFor
UnregisterDisplay[None|Contents]StyleFor okay, this is actually two functions, but they act as a pair
This change makes all these functions call GetApplicableParent up front and act on and pass around the parent that it returns. This is so that throughout the code we are always handling the parent that will be used as the key in the UndisplayedMap entry. This is necessary so that all the code that sets/gets the 'MayHaveChildrenWithLayoutBoxesDisabled' bit on/from an nsIContent object is using the same object, otherwise everything breaks down.
Partially based on part 2 of https://bugzilla.mozilla.org/show_bug.cgi?id=1367214
This introduces the `ParentForUndisplayedMap` helper method to reduce duplication in terms of getting the parent and asserting parent existence.
Partially based on parts of https://bugzilla.mozilla.org/show_bug.cgi?id=1341083
Changing to vector makes manipulating display list items more risky.
This is to make sure we don't inadvertently end up with duplicates in
the list of display items avoiding double-free scenarios.
This removes the need to keep the `flex-basis` handling code of the ComputeSize* functions in sync since they both call the same function now for this purpose.
This implements flexbox layout for the gap properties without the refactoring work performed on `nsFlexContainerFrame`.
Partially based on https://bugzilla.mozilla.org/show_bug.cgi?id=1398483 and https://bugzilla.mozilla.org/show_bug.cgi?id=1454822
This excludes the second part of bug 1454822, the width caching implementation, because it is out of scope and currently causes unstable layout with `writing-mode: vertical-lr` (see bug 1709937).
This removes the `grid` prefix from the gap-related properties of grid since they are now part of the box alignment specification. Former grid-gap* properties were aliased to the unprefixed properties to maintain compatibility.
The previously multi-column layout only `column-gap` property has been modified to apply to the Grid layout (and Flexbox in a following commit), moving the `mColumnGap` member variable from `nsStyleColumn` to `nsStylePosition`.
Notes:
* Bug 1398537 - support for percent values in column-gap for multi-column layout landed as part of Issue #1230. However, it was incomplete because it did not update `nsRuleNode` to allow transformation of percentage values for `column-gap`. This was consequently fixed as part of this commit.
* Bug 1456166 - this might not apply because we don't have that devtools test in UXP
* `nsRuleNode`, `nsCSSParser`, `Declaration`, and other related classes were merged into Stylo. These should be taken into consideration when porting patches from Mozilla.
Partially based on https://bugzilla.mozilla.org/show_bug.cgi?id=1398482
This functionality was already added to Gecko for UA stylesheets allow the "dom.details_element.enabled" preference to work. I changed the condition to allow bool preferences to be used in chrome stylesheets as well.
The removal of this preference was botched, all other surrounding plumbing changes appear to be working okay. The ability to use prefs to control this stylesheet might be useful in the future, so perhaps this is one of those "if it ain't broke, don't fix it" bugs where leaving well enough alone in the first place would have been the best choice.
This PR passes all current tests for this feature, and implements the "prefers-color-scheme" media query as an enumerated keyword that is controlled by an integer preference.
Currently, the possible options are 0 to see a website's fallback code and essentially behave like this isn't implemented (our current behavior), 1 to express a preference for a light theme (the default for spec reasons), and 2 to express a preference for a dark theme. Over time, this list may expand to include other preferences like a preference for a sepia theme or something, and this leaves us prepared for that future.
With the changes to layout for WebComponents, it is now apparently possible to
pass in null for frame tree items to this function, which would cause a null
deref crash if not checked.
This feature should not be shipped until the various definitions of addition for
each additive property are properly specified and then implemented accordingly.
Unlike other patches in this series, compositing is not frequently used
internally so there is no need to enable this by default for chrome callers.
